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Denys Vlasenko 44f87efc67 Remove tcp->parent and TCB_CLONE_THREAD. tcp->parent is used for only two things: (1) to send signal on detach via tgkill (need to know tgid). Solution: use tkill, it needs only tid. (2) to optimize out ptrace options setting for new tracees. Not a big deal if we drop this optimization: "set options" op is fast, doing it just one extra time once per each tracee is hardly measurable. TCB_CLONE_THREAD is a misnomer. It used only to flag sibling we attached to in startup_attach. This is used to prevent infinite recursive rescanning of /proc/PID/task. Despite the name, there is no guarantee it is set only on non-leader: if one would run "strace -f -p THREAD_ID" and THREAD_ID is not a thread leader, strace will happily attach to it and all siblings and will think that THREAD_ID is the leader! Which is a bug, but since we no longer detach when we think tracee is going to die, this bug no longer matters, because we do not use the knowledge about thread group leaders for anything. (We used it to delay leader's exit). IOW: after this patch strace has no need to know about threads, parents and children, and so on. Therefore it does not track that information. It treats all tracees as independent entities. Overall, this simplifies code a lot. * defs.h: Add TCB_ATTACH_DONE flag, remove TCB_CLONE_THREAD flag and struct tcb::parent field. * process.c (internal_fork): Don't set tcpchild->parent. * strace.c (startup_attach): Use TCB_ATTACH_DONE flag instead of TCB_CLONE_THREAD to avoid attach attempts on already-attached threads. Unlike TCB_CLONE_THREAD, TCB_ATTACH_DONE bit is used only temporarily, and only in this function. We clear it on every tcb before we return. (detach): Use tkill instead of tgkill. (trace): Set ptrace options on new tracees unconditionally, not only when tcp->parent == NULL. Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>		2011-08-17 15:18:21 +02:00
debian	Prepare for 4.6 release	2011-03-14 15:39:36 +00:00
freebsd	Remove obsolete .cvsignore files	2011-02-25 16:53:50 +00:00
linux	Fix MIPS syscall entries	2011-06-09 15:16:01 +00:00
m4	Fix off_t/rlim_t size checks when cross-compiling	2010-09-15 15:36:00 +00:00
sunos4	Whitespace cleanups. no code changes.	2011-06-07 12:13:24 +02:00
svr4	Whitespace cleanups. no code changes.	2011-06-07 12:13:24 +02:00
test	Add fflush after printf in test/sigkill_rain.c	2011-06-08 16:07:03 +02:00
tests	tests: finish ptrace_setoptions_* merge	2011-06-21 15:03:17 +00:00
.gitignore	linux/ioctlent: unify them all	2011-03-14 15:32:38 +00:00
.mailmap	Generate much of the CREDITS file from git log	2011-02-24 01:51:15 +00:00
AUTHORS	2002-12-22 Roland McGrath <roland@redhat.com>	2002-12-30 00:51:30 +00:00
bjm.c	Whitespace cleanups. no code changes.	2011-06-07 12:13:24 +02:00
block.c	Fix compilation on 2.4.20 kernel based system	2011-08-15 11:36:09 +02:00
ChangeLog-CVS	Generate ChangeLog from git log	2009-07-08 21:01:21 +00:00
configure.ac	Check for additional PTRACE_* constants	2011-07-19 22:13:11 +00:00
COPYRIGHT	update copyright	2002-03-31 18:43:00 +00:00
count.c	Whitespace cleanups. No code changes.	2011-06-22 14:32:43 +02:00
CREDITS.in	* CREDITS.in: Fix typo.	2011-03-15 15:46:52 +00:00
defs.h	Remove tcp->parent and TCB_CLONE_THREAD.	2011-08-17 15:18:21 +02:00
desc.c	Whitespace cleanups. No code changes.	2011-06-22 14:32:43 +02:00
errnoent.sh	Mark shell scripts as executable	2009-09-18 12:07:03 +00:00
file.c	Whitespace cleanups. No code changes.	2011-06-22 14:32:43 +02:00
git-set-file-times	* git-set-file-times: Import from rsync.	2009-10-09 23:07:28 +00:00
gitlog-to-changelog	Generate ChangeLog from git log	2009-07-08 21:01:21 +00:00
HACKING-scripts	HACKING-scripts: new doc file by Mike Frysinger	2009-02-23 07:56:01 +00:00
INSTALL	Cleanup trailing whitespaces and indentation that uses spaces before tabs	2009-07-08 14:57:27 +00:00
io.c	Add argument to tprint_iov() specifying whether to decode each iovec	2011-06-13 22:58:44 +00:00
ioctl.c	Introduce ARRAY_SIZE() macro	2011-06-13 21:58:43 +00:00
ioctlsort.c	Fix const-correctness issues uncovered by gcc -Wwrite-strings	2010-09-07 00:59:18 +00:00
ipc.c	Whitespace cleanups. no code changes.	2011-06-07 12:13:24 +02:00
make-dist	Generate an xz tar archive of the distribution	2011-02-27 14:05:58 +00:00
Makefile.am	Add ability to print file descriptor paths and filter by those paths	2011-04-08 20:47:56 +00:00
mem.c	Whitespace cleanups. no code changes.	2011-06-07 12:13:24 +02:00
net.c	Whitespace cleanups. No code changes.	2011-06-22 14:32:43 +02:00
NEWS	Prepare for 4.6 release	2011-03-14 15:39:36 +00:00
pathtrace.c	Whitespace cleanups. No code changes.	2011-06-22 14:32:43 +02:00
PORTING	Initial revision	1999-02-19 00:21:36 +00:00
proc.c	"Modernize" all old-style function parameter declarations	2011-05-30 14:00:14 +02:00
process.c	Remove tcp->parent and TCB_CLONE_THREAD.	2011-08-17 15:18:21 +02:00
quota.c	Whitespace cleanups. No code changes.	2011-06-22 14:32:43 +02:00
README	More cleanups from Mike Frysingler:	2009-02-23 08:07:45 +00:00
README-freebsd	trailing whitespace removal, no code changes	2009-01-02 13:03:44 +00:00
README-hacking	Generate ChangeLog from git log	2009-07-08 21:01:21 +00:00
README-linux	Cleanup trailing whitespaces and indentation that uses spaces before tabs	2009-07-08 14:57:27 +00:00
README-sunos4	Initial revision	1999-02-19 00:21:36 +00:00
README-svr4	Cleanup trailing whitespaces and indentation that uses spaces before tabs	2009-07-08 14:57:27 +00:00
resource.c	Handle biarch get/setrlimit	2010-07-17 17:46:28 +02:00
scsi.c	2007-03-29 Vladimir Nadvornik <nadvornik@suse.cz>	2007-06-30 11:37:09 +00:00
signal.c	Do not detach when we think tracee is going to die.	2011-08-17 10:45:32 +02:00
signalent.sh	Mark shell scripts as executable	2009-09-18 12:07:03 +00:00
sock.c	Whitespace cleanups. no code changes.	2011-06-07 12:13:24 +02:00
strace-graph	Cleanup trailing whitespaces and indentation that uses spaces before tabs	2009-07-08 14:57:27 +00:00
strace.1	Add ability to print file descriptor paths and filter by those paths	2011-04-08 20:47:56 +00:00
strace.c	Remove tcp->parent and TCB_CLONE_THREAD.	2011-08-17 15:18:21 +02:00
strace.spec	Prepare for 4.6 release	2011-03-14 15:39:36 +00:00
stream.c	Whitespace cleanups. no code changes.	2011-06-07 12:13:24 +02:00
syscall.c	Do not detach when we think tracee is going to die.	2011-08-17 10:45:32 +02:00
syscallent.sh	Mark shell scripts as executable	2009-09-18 12:07:03 +00:00
system.c	* system.c (sys_capget, sys_capset): Fix pointer arithmetics	2011-06-23 13:25:09 +00:00
term.c	Remove dead code	2010-02-04 22:40:57 +00:00
time.c	Whitespace cleanups. No code changes.	2011-06-22 14:32:43 +02:00
TODO	Merge iov fixes from Richard Kettlewell	2001-07-10 13:48:44 +00:00
util.c	Untangle a particularly badly obfuscated bit of code. No logic changes.	2011-06-23 21:57:54 +02:00
xlate.el	Initial revision	1999-02-19 00:21:36 +00:00

README

This is strace 4.0, a system call tracer for SunOS 4.x, Linux, System
V release 4, Solaris 2.x and Irix 5.x.  strace is released under a
Berkeley-style license at the request of Paul Kranenburg; see the file
COPYRIGHT for details.

Read the INSTALL file for generic instructions on how to install
strace.  If configure cannot guess your system configuration, you can
specify it on the command line after the other options like this:

	./configure --prefix=/usr i486-linux

A single sunos4.1 binary should work on all the sun4, sun4c and sun4m
kernel architectures.  Let me know if sun4d doesn't work.  Other
i486-*-sysv4 systems may work with little or no tweaking.

See the file NEWS for information on what has changed in recent
versions.

See the file PORTING if you like strace but it doesn't work on an
operating system you use frequently.

See the file CREDITS to see who has contributed to strace.

See the file TODO if you feel like helping out.

You can get the latest version of strace from its homepage at
http://sourceforge.net/projects/strace/ .

Please send bug reports and enhancements to the strace
mailinglist at strace-devel@lists.sourceforge.net, or directly to
Wichert Akkerman <wakkerma@debian.org>